Constructing droplet interface bilayers from the contact of aqueous droplets in oil.

Journal article

We describe a protocol for forming an artificial lipid bilayer by contacting nanoliter aqueous droplets in an oil solution in the presence of phospholipids. A lipid monolayer forms at each oil-water interface, and when two such monolayers touch, a bilayer is created. Droplet interface bilayers (DIBs) are a simple way to generate stable bilayers suitable for single-channel electrophysiology and optical imaging from a wide variety of preparations, ranging from purified proteins to reconstituted eukaryotic cell membrane fragments. Examples include purified proteins from the α-hemolysin pore from Staphylococcus aureus, the anthrax toxin pore and the 1.2-MDa mouse mechanosensitive channel MmPiezo1. Ion channels and ionotropic receptors can also be reconstituted from membrane fragments without further purification. We describe two approaches for forming DIBs. In one approach, a lipid bilayer is created between two aqueous droplets submerged in oil. In the other approach, a membrane is formed between an aqueous droplet and an agarose hydrogel, which allows imaging in addition to electrical recordings. The protocol takes <30 min, including droplet generation, monolayer assembly and bilayer formation. In addition to the main protocol, we also describe the preparation of Ag/AgCl electrodes and sample preparation.

Authors: Leptihn, S; Castell, O; Cronin, B; Lee, E; Gross, L

• Publication status: Published
• Journal: Nature protocols
• Volume: 8
• Issue: 6
• Pages: 1048-1057
• Publication date: 2013-06-01
• DOI: 10.1038/nprot.2013.061
• EISSN: 1750-2799
• ISSN: 1754-2189
• Language: English
• Keywords: Silver; Ion Channels; Hemolysin Proteins; Bacterial Toxins; Lipid Bilayers; Silver Compounds; Water; Animals; Mice; Oils; Membranes, Artificial; Alkanes; Antigens, Bacterial; Nanostructures